<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>伪类和伪元素</title>
    <style>
        * {
            background: green;
            color: #ffe75e;
            font-weight: bold;
            font-size: 30px;
        }

        input {
            display:block;
            margin: 10px auto;
            width: 100px;
            height: 100px;
        }

        input::after {
            content: "已勾选";
            display: none;
            width: 150px;
            height: 50px;
            margin-left: 110px;
        }
        input:checked::after{
            display: block;
        }
    </style>
</head>
<body>
<input type="checkbox">
<input type="checkbox">
<input type="checkbox">
</body>
</html>